1. Field of the Invention
This invention relates generally to a building construction assembly composed of plastic structural modules which are interconnectable to create the shell of a residential or other edifice, and in particular to an assembly of this type in which the modules are interconnected by snap-in joiners to create the walls of the shell.
2. Status of Prior Art
The need for low cost housing that is available on short notice becomes most pressing when there is an influx of people into a community who are in search of such housing but cannot afford the cost of standard housing, nor can they wait out the prolonged period it normally takes to construct a standard house.
Such a situation arose at the conclusion of World War II when thousands of veterans returned to their towns and villages to rejoin or acquire wives and to find a suitable residence for their families. U.S. Pat. No. 1,958,124 is addressed to this situation, for it discloses a building construction assembly composed of factory-manufactures block-like hollow steel modules which when interconnected at a building site create the basic shell of a livable residence.
But the commercial acceptance of a construction assembly of steel modules was not widespread, for it was discouraged by the need to weld together a multitude of such modules. This requirement added substantially to the cost of erecting the steel shell of the edifice and the time it took to do so.
Of greater prior art interest is the 1999 U.S. Pat. No. 5,729,944 to De Zen which deals with an assembly of interconnectable thermoplastic structural components, adapted to create the shell of an edifice, as does a construction assembly in accordance with the present invention.
The structural components disclosed in the De Zen patent are each provided along its length with grooves adapted to mate with interlocking flanges of a box connector serving to interconnect adjacent components. A serious drawback of the De Zen arrangement is that it is necessary to slide the elongated structural components into the box connectors and it is difficult to do so at a building site. Also of prior art interest are De Zen U.S. Pat. Nos. 5,706,620 and 5,974,751 which show construction assemblies similar to those in the De Zen '944 Patent.
There are known also building structures disclosed in U.S. Pat. 5,247,773. In this patent are described modular structural components extruded from plastic. The structures are used for building a wall, ceiling, roof etc. The structures can be connected by virtue of male and female means provided on the middle of short, transversal walls of the modules. For this purpose the male component of one module has resilient flanges that can be forced into a corresponding female slot of the adjacent module. Relevant to the present invention is the embodiment shown in FIG. 9,10 depicting a dedicated joiner consisting of two male locking protrusions facing in opposite directions and adapted for insertion into corresponding female depressions made in the modules. The disadvantage of this solution lies in the fact that relatively high forces should be applied to join the modules, since the force is to be applied perpendicularly to the transversal wall of the module and it should be sufficient to deflect both resilient flanges of the male component, the outcome of which is that assembly becomes complicated and inconvenient. This renders the assembling complicate and inconvenient. Furthermore, the disposition of the female depressions on the middle of the transverse wall allows to join the modules merely in side-by-side relationship and not in a cross relationship.